He got lucky in 2005, walking away from assault, larceny and robbery charges after Hampden County prosecutors could not coax a witness into testifying at trial.

He was luckier this week, when his second-degree murder case was thrown out after the main witness disappeared.

Sixteen months after being charged in the bludgeoning death of his sister’s boyfriend, the 28-year old city man was swarmed by jubilant family members in the hallway of Hampden Superior Court on Tuesday. Moments earlier, Judge Cornelius J. Moriarty had rejected a prosecutor’s latest request for more time to locate the witness and dismissed the case.

“This is very unusual,” said Bruce Green, one of Alexander’s defense lawyers, after the brief hallway celebration ended. “It happens – but I’ve never seen it happen.”

For Alexander, the outcome was even sweeter than the 2004 decision by the office of Hampden District Attorney William M. Bennett to drop charges in a larceny, assault and robbery case for lack of a willing witness. At the time, assistant district attorney Christine Tetreault said the witness could not testify, but would not elaborate.

Even with two dropped cases on his rap sheet, Alexander has not led an entirely charmed life in the court system.

At 17, he made his first appearance in a Superior Court as a defendant in a marijuana and burglary case. In 2002, he was sentence to two years in the Hampshire House of Correction after being convicted for selling a $50 rock of crack cocaine to an undercover officer in Ware.

And in 2005, Alexander was arrested again for selling crack cocaine in the parking lot of a McDonald’s restaurant in Ware. His co-defendant was his cousin Chad Alexander, now 37 and living in Florida.

Duran Alexander’s next case had nothing with drugs.

In July 2009, he was charged with a fatal baseball bat attack on Emilo Marty, 39, of 293 Walnut St. Police reports indicate the victim was dating Alexander’s older sister, and got into a dispute with her in his driveway on May 29.

When Alexander arrived on the scene, he posed what turned out to be a rhetorical question, according to the report: “You really gonna kill my sister, Loco?” he said, according to the witness whose disappearance later crippled the case.

The police report said Alexander picked up a baseball bat, and hit Marty once in the back of the head, according to the witness. The witness told police a gold minivan arrived moments later and took Alexander away, according to the report.

After two months as a fugitive, Duran Alexander was arrested in Hardwick and held without right to bail for eight months; when his June trial date arrived, the case was put on hold to allow prosecutors to find the missing witness; the next date was set in early November, but no witness was found.

To defense lawyer George M. Nassar, dismissing the case was the only fair option.

Alexander was only defending himself and his sister against someone with a reputation and long history of violence, Nassar said. “They don’t call him Loco for nothing,” he said, adding that Marty served prison time for assaulting another member of Alexander’s family.

“He a crazy, violent man, known to carry a machete or a knife or a gun,” Nassar said. “The relationship (between Alexander’s sister and Marty) was very turbulent, volatile one” the lawyer added.

Before Moriarty threw out the case, assistant district attorney Donna Donato acknowledged that the witness could not be located, and asked for one more month.

Moriarty dismissed the case without prejudice, meaning prosecutors can refile charges if they locate the witness.

Either way, the chances of winning a conviction are slim, Nassar believes.

“They don’t have a case. I don’t think they had a case even with the witness,” he said.